We are PCD Support UK. We’re here for those affected by PCD, we talk about PCD as widely as possible and we champion research to improve its diagnosis, management and treatment. Primary Ciliary Dyskinesia (PCD) is a rare, genetic disease affecting around 1 in 15,000 people in the UK. It's caused by abnormal motile cilia (motile cilia are the microscopic hairs that beat in the airways, sweeping secretions out of the respiratory tract). PCD can affect the lungs, nose, sinuses, ears and fertility and causes recurrent respiratory infections.